Reversible internal-combustion engine



y F. T. CABLE REVERSIBLE INTERNAL COMBUSTION ENGINE 2. Sheets-Sheet 1 Filed March 18, 1924 I INVENTOR )ZZM/M May 3 1927.

1,627,316 F. T. CABLE REVERSIBLE INTERNAL COMBUSTION ENGINE Filed March 18, 1924 2 Sheets-Sheet 2 J 47 45 l ,L

INVENTOR ATTORNEY Patented May 3, 1927.

UNITED! PATENT OF icE.

FRANK renew, OF NEW LONDON, CONNECTICUT, AssIG OR r0 ELECTRIC BOAT COMPANY, OF GROTON, CONNECTICUT, A CORPORATION OF NEW JERSEY.

REVERSIBLE INTEnNAn-o MB s'rION ENGINE.

Application filed March 18,1924. Serial NO. 699,375.

This invention relates to four-cylinder internal combustion engines, and more partic-- ularly to a four-cylinder engine of the wellknown Diesel type, which is diflerent from the ordinary four-cylinder Diesel engine in that it is reversible,

Reversible Diesel engines having more than four-cylinders are now in common use, but heretofore it has not been considered possible to makea satisfactory fourcylinder reversible internal combustion engine ofthis type, due to the fact that two of the engine pistons are connected to cranks spaced 180- apart from the remaining cranks of the crank shaft, and consequently the crank shaft occasionally stops'on dead center. Accordingly four-cylinder Diesel engines cannot be used'for many purposes unless reversing gears are provided, so as to permit the engine to run' in the same direction at all times. a y

The present invention was devised with a view to providing means whereby a four:- cyl-inder Diesel engine can be stopped and started in the reverse direction with very little effort and in a very short period of time. In general, my invention comprises means permanently associated with afourcylinder engine whereby the crank shaft can be turned away from its dead center position so that the engine can be started in either direction as determined by the position of theengin'e camshafts, by admit-- ting compressed air tothe engine cylinders in'theusual manner. The invention includes means formoving the crank shaft away from its dead center position by a step by step movement which is used only in the event that the crankshaft stops within 10 of this position, and additional means for quickly moving the crank shaftaway from its dead center position when the shaft occupies a position at an angle of 10 or more away from its dead center position. The invention also includes means for indieating at all times. the positionof the engine crankshaft,

This invention can be best understood by considering the following detaileddescription which is to be taken in conjunction with the accompanying drawings, in .which Fig. 1 is a'perspective view ofia fourcylinder Diesel engine embodying my invention. y y

Figs. 2 and 3 are diagrammatic views,

partly in section, illustrating; the operation of apart of my: invention, and a I Figs. 4 to 7 incll, are diagrammatic views of: a crank shaft showing the manner ,in which myv invention operates toturn the crank shaft away from its dead-center posi tion.

The four-cylinder Diesel engine illusr' tratedin' Fig.1 of the accompanying drawings comprises fourvertical cylinders 1 surdrawn into the cylinders, a suitable slotted intake member 5 being provided on the ex terror of each engine cylinden A fuel .valve: 6is provided at the top of each cylinder near thelcenter thereof in accordance with the usualrpractice. An. exhaust valve 7 is provided for each cylinder,-opposite the intake valve 4, the four exhaust valves communicating with an exhaust manifold 8. Each of the intake valves 4 is actuated by a vertical lever 9'which carries-a cam follower at the lower endthereof whichcooperates with the cam shaft 10. In like manner,hthe exhaust valves 7 are connected to a cam shaft 11 bymeans of levers 12. Each ofthe fuel valves 6 is actuated bya lever 13 which in turn-is actuated by avertical lever l4 cooperating with: the cam shaft 10. I A relief valve 4" is provided-in each of the engine cylinders 1, these valves being operated by, means of a relief valve operrating. rod 5.

A number of' details have been purposely omitted from the drawings in order to avoid complicating the drawings unnecessarily.

of these air starting valves is actuated'by a lever similarto the levers 13, and that a sultable starting lever is provided for the purpose of placing the starting valvesin condition to operate and. permitting the fuel valves to remain closed. during the.

starting. period. Other details which have ibeencpurposely omitted from-the drawin inclu S e the ordinary pipe connections tO-tEe fuel valves, the exhaust pipe leading away from the manifold 8, the air compressor, and the compressed air tanks.

The details which have been described above, with the exception of the cam shafts 1,0 and 11, are of ordinary standard con-.

struction. and form a part of every fourcylinder Diesel engine. The following detailed description relates to the novel features I have provided in orderto make the four-cylinder engine reversible.

The cam shafts and 11 referred to above are provided with adouble set of cams for causing the engine to operate in one direction or the other as determined by the operator. A hand lever 15 is provided for the purpose of shifting these cam shafts axially so as to bring either set of cams into position opposite the cam followers carried by the vertical levers?) and .14. Suitable con necting linkages 16 are provided between the hand lever 15 and the cam shafts. The two cam shafts are driven through suitable gear connections (not shown) connecting these shafts to the engine crank shaft, one end of which is shown at 17. An indicator is provided for the purpose of showing the operator at all times the position of the engine crank shaft. This indicator, which may consist of a dial 18, pointer 19 and suitable mechanism for turning the pointer, can be geared to one of the cam shafts as shown at 20. The dial 18 may be specially marked, for example as indicated in Fig. 1, for the purpose of showing whether or not the engine crank shaft is within a predetermined angle, for instance 10 of its dead center position. hen the form of indicator shown in Fig. 1 is employed, it is adjusted so that when the pointer 19 comes to rest over the shaded portion 21 of the dial, the engine crank shaft is within. approximately*10 of its deadcenter position. i

It will be appreciated that to provide a four-cylinder Diesel engine with reversing cam shafts such as the shafts 10- and 11, and with an engine crank shaft indicator such as that just described, would not be of great value, unless some means were provided for shifting or turning the engine crank shaft away from its dead center position far enough so that the engine can be started in either direction, as determined by the positions of the cam shafts, by admitting compressed air to the starting valves in the usual manner. Accordingly, I have provided two means for shifting the engine crank shaft, these means being permanently associated with the engine and cooperating to provide'a thoroughly reliable system for rendering the four-cylinder engine reversible. In general, these two devices consist of a fluid pressure apparatus adapted to jack the engine crank shaft, around, and means for supplying compressed air to two cylinders of the engine, containing pistons connected to cranks disposed 180 apart.

' The pipe 22 leads from the ordinary compressed air tanks (not shown) which are used in starting the engine. Thispipe is connected to two cylinders of the engine by means of a main pipe connection 23 and short lateral connections 24; and 25. Suitable valves 26, 27 and 28 are provided for the purpose of regulating the How of com pressedair to these cylinders. This air connection can be made to any two of the engine cylinders containing pistons connected to cranks which are 180 apart.

The operation of the air connection system just described can be best understood by referring to Figs. 1 and etto 7 incl. If the valves 27 and 28 are open, the effect of opening the valve 26 in the air supply pipe 23' is to admit compressed air. to two cylinders of the engine. This air will exert a force on the two pistons within these cylinders, which, it will be remembered, are connected to cranks 108 apart, and unless the engine crank shaft is within less than approximately 10 from its dead center position, the compressed air will expand and force the crank shaft away from itsdead center position. For example, if the crankshaft 17' of Figs. 41- to 7 incl. is slightly off dead center, as shown in Fig. 6, and the compressed air exerts its force against pistons 29 and 30, the air will expand and forcethese pistons to move until they occupy the position shown in Fig. 7 or, in other words, until the crank shaft has been turned approximately. The force exerted upon these pistons by the compressed air causes them to move untilthe combined volume of the spaces within the eylinderscontaining the compressed air, is a maximum, which of course is when the pistons occupy the position shown in Fig. 7.

It is, of course, true that where two pistons connected to cranks 180 apart are within say 10 ofthe dead center position, the free space in one of the cylinders is much greater than that in the other. Therefore, when compressed fluid, such as air, is admitted to these two cylinders, thopressin'e will build up faster in the cylinder having the smaller amount of-free-spahe above the piston than it will in the other cylinder. This will start the crank shaft rotating toward a position away from the dead center position. But even if the pressure were the same in both cylinders, there would still be a strong tendency to rotate the crank shaft away from its dead center position. This can be forces at right angles to the cranks of the crank shaft. i

If the engine crank shaft is on exactly 38 which dead center, asshown in Fig. 5, or within approximately 10 of this position, the position' of the crank shaft-cannot he changed by merely admitting compressed air to two engine cylinders in the manner above de scribed, In order to take care of this contingency I prefer to use means permanently associated with the engine for jackingthe engine crank shaft around. In the embodt mentof. the invention illustrated in the ac companying drawings I have provided a ratchet wheel 31 fixed with respect to the engine crank shaft 17. This ratchet: wheel can be fixed to the engine crank shaft directly, ratchet wheel 31 is adapted to be engaged by a .pawl33 carried by a,yoke 34, which is .ro-. tatably mounted on the engine crank shaft. The pawl 33 is pivoted to the yoke near the closed end thereof, by means ofa bolt 35.

The outer or closed end of the yoke 34 is connectedto a piston rod 36 in any suitable manner, for example by means ofthe bolt 37. The

' is pivoted on a stationarylsupport 39carried by the bed plate 3. The endof the cylinder 38 through which the piston rod 36 projects is closedby a cap 40 (see Fig. 2) which has alug 41 thereon adapted to cooperate with a lug 42 carried by the pawl33.- "These partsare arranged so that when the two lugscome together, the pawlis lifted from the ratchet wheel 31 and this wheel is free to rotate in either direction. The piston 43 connected to the piston rod 36 is moved back and forth within the cylinder 38 byadmittingcompressed air into one end of the cylinder and connecting the other end to atmosphere andthen reversing this process. Accordingly, air connections in the form of pipes 44 and'45 are provided, extending between the cylinder'38 and the main compressed air supply pipe 22. The supply of con'ipressed air to these C01111e0- tions 44'and 45 is controlled in thefirst instance by a valve 46 in the main supply pipe 22." In addition, a four-way valve 47 18 provided at the point where the two supply pipes 44 and 45 are connected to the main supply pipe 22. This four-way valve or cock is provided with a handle or lever 48 by'means of which the valve can be turned to connect the supply pipe 22 to either of the pipes 44 M45, and simultaneously to these pipes to the atmosphere through a suitable vent 49. With the hand lever in the position shown in F ig. 2, the compressed air from the pipe 22 is admitted to pipe 44 which conducts the air to the lower end of the cylinder 38. The

other pipe 45 is connected to the atmosphere.

hev compressed air forces the piston 43 upward, the initial movement thereof cans mg the lugs 41 and 42 to become disengaged to allow the pawl 33 to drop into engageend of the cylinder 38.

or to the engine fly wheel 32. The

carried thereby,

piston rod projects intoa cylinder lever which controls meiitw'ith the ratchet wheel-31 and the continned movement of the piston rod 36 turning the ratchet wheel 31, and consequently theengine crank shaft 17, until the piston 43 has reached the end of itstravel, as shown in Fig; 3. ,If the hand lever 48is then'moved to the position shown'in Fig.- 3'. the compressed air in the lower ,part'of the cylin'der 38' is discharged into the at mosphere through the vent49 andtheiair supply pipe 22 is connected to the pipe 45 whichcondiicts compressed air to the upper This forces the piston 43 to the lower end of' the cylinder 38 and brings the yoke '34, and the pawl 33 back to their initial-positions. By movingthe hand lever 48'ba'ck andforth, from one extreme positionto the other, the engine crank shaft can be jacked aroundto anydesired extent, the position of the. crank shaftbeing indicated at-all'times by. the pointer 19.

" "I have found that: it'is seldom necessary to use the fluid pressure jackingdevice for continuing thejacking operation. In either air admitted to event the time consumed in movingthe en- I gine crank shaft far enough away from its dead. center posit on so that 1t. can-be started by admitting compressed air to theengine cylindersin the usualinanner, requires only a' few moments. In order to reverse the direction of rotation, it is only necessary to shift the cam shafts, axially, when the engine' is at rest.

pressed air into the engine cylinders in the usual manner,'that is by manipulating the. the operation of the air starting valves. p It is to be understood that the details of my invention can be modified without departing from the spirit of the invention which is not limited to the particular em,- bodiments illustrated and described, but in- .cludes such modifications thereof as fall within the scope of the appended claims.

While my invention has been described as applied to a four-cylinder Diesel engine,

Then when the engine crank shaft has been turned away from its it may of course be used to advantage with four-cylinder engines of other types. It is particularly useful with Diesel engines for in this case it is not necessary to provide a special source of compressed air, the compressed air supply tanks used in starting the engine being suitable for supplying compressed air to two cylinders of the engine and to the jacking device in the manner above described.

I claim: A

1. An internal combustion engine comprising at least two engine c linders, pistons in said cylinders,a crank shaft having two cranks spaced 180 apart, means for connecting the cranks to the pistons, means for reversing said engine including a reversing shaft, fluid starting means for said engine, means for forcing the crankshaft away from a position near its dead center posi tion including fluid pressure connections for simultaneously admitting compressed fluid to the two cylinders of the engine having the pistons connected to the cranks spaced 180 apart, whereby said pistons are brought into substantially the same horizontal plane and the engine adapted to be started in either direction.

2. An. internal combustion engine comprising four engine cylinders, pistons in saidv cylinders, a crank shaft, two of the cranks of said crank shaft being spaced 180 apart, means for connecting the cranks to the pistons, means for reversing said engine including a reversing shaft, fluid starting means for said engine, means for forcing the crank shaft away from a position near its dead center position including fluid pressure connections for simultaneously admitting compressed fluid to the two cylinders of the engine having the pistons connected to the cranks spaced 180 apart, and a valve for admitting compressed fluid to said connections simultaneously, whereby said, pistons may be brought into substantially the same horizontal. planefand the engine adapted to be started in either direction. F g

8. An internal coibnstion engine comprising four engine cylinders, pistons in said cylinders, a crank shaft, two of the cranks of said crank shaft being spaced 180 apart, means for connecting the cranks to the pistons,means for reversing said engine including a reversing shaft, fluid starting means for said engine, means for jacking the engine crank shaft around when it is on cylinders of the engine having starting means for said engine, fluid sure connections to the two cylinders of the through said pipe connection. whereby the L crank shaft can be moved further away from its dead center position, thepistons brought into substantially the same horizontal plane andthe engine started in either direction, r

4t. An internal combustion engine comprising four engine cylinders, pistons in said cylinders, a crank shaft, two of the cranks of said crankshaft being spaced 180 apart, means for connecting the cranks to the pistons, means for reversin said engine including a reversing shaft, fluid starting means for said engine, means for jacking the engine crank shaft around when it is on substantially dead center whereby the crank shaft can be turned through a small angle away from its dead center position, means for admitting compressed fluid to the two the pistons connected to the cranks which are spaced 180 apart to force the crank shaftifurther from its dead center position, and bring the pistons in said cylinders into substantially the same horizontal plane so that the engine may be started in either direction, and means for indicating the position of the engine crank shaft. 7 g V 5. An internal combustion engine comprising four engine cylinders, a crank shaft,

two of thecranksof said crank shaft being spaced 180 apart, means for connecting the cranks'tothe plstons, means for reversing said eng ne including a reversing shaft, fluid resengine having the pistons connected to the cranks which are spaced 180 apart, and a valve for admitting compressed fluid to these connections whereby the crank shaft can be moved away from its dead center position and the pistons connected to the cranks spaced 180 stantially the same horizontal plane and the engine started in either direction.

In test mony whereof I aflix my sigi'iature.

FRANK r. CABLE.

apart brought into sub 

